Despite what people may say the internet we knew 20 years is still there, anybody can throw up a website and make a presence for their club, charity, shop or even themselves. Most people don't however, and still continue to use many of the same big tech services because "it's free" or "it's what everyone else uses". The unspoken truth here is that these same companies can remove you from their services automatically, without appeal or reprocussion and all of the data you had stored with them goes with it.
5hm is a nerds pet project to prove the internet can still function even without big tech and provide some no nonsence SAAS and advice to encourage a more diverse internet.